Diabetic Ocular Surface Has Defects in Oxygen Uptake Revealed by Optic Fiber Microsensor

摘要: Purpose: Diabetes mellitus causes diabetic keratopathy (DK). This and other ocular surface disorders are underdiagnosed and problematic for affected patients as well as recipients of diabetic donor corneas. Thus, it is important to find noninvasive means to facilitate determination of the potentially vision-threatening DK. It has been reported that diabetic corneas uptake significantly less oxygen (O 2) than healthy controls. However, an integral assessment of the ocular surface is missing.Methods: Using an optic-fiber O 2 micro-sensor (optrode) we demonstrated recently that the healthy ocular surface displays a unique spatiotemporal map of O 2 consumption. We hypothesize that diabetes impairs the spatiotemporal profile of O 2 uptake at the ocular surface.Results: Using streptozotocin (STZ)-induced diabetic mice, we found diminished O 2 uptake and loss of the unique pattern across the ocular surface. A diabetic cornea consumes significantly less O 2 at the bulbar conjunctiva and limbus, but not the central and peripheral cornea, compared to controls. Further, we show that, contrary to the healthy cornea, the diabetic cornea does not increase the O 2 consumption at the limbus in the evening as the normal control.Conclusions: Altogether, our measurements reveal a previously unknown impairment in O 2 uptake at the diabetic cornea, making it a potential tool to diagnose ocular surface abnormalities and suggesting a new etiology mechanism.